Substituted-ureido derivatives of penam 3-carboxylic acid and cephem 4-carboxylic acid

ABSTRACT

6-Acylamino-penam-3-carboxylic acids and 7-acylamino-3-cephem-4-carboxylic acids in which the acyl group has the formula ##EQU1## in which R 1  is hydrogen, R 2  is optionally substituted phenyl, thienyl or furyl, or R 1  and R 2  together are optionally substituted cycloalkyl, and B is a radical which is bonded via a sulphur atom or is bonded to oxygen or sulphur with the interposition of an optionally substituted CH 2  -group.

The invention relates to new therapeutically valuable derivatives of6-amino-2,2-dimethyl-penam-3-carboxylic acid and of7-amino-ceph-3-em-4-carboxylic acid and their salts, processes for theirmanufacture and pharmaceutical preparations which contain the newcompounds.

The new compounds have the general formula I ##EQU2## wherein thegrouping --S--A-- represents a radical of the formula Ia or Ib ##EQU3##WHEREIN R₃ denotes an optionally protected carboxyl group and R₄represents hydrogen or an optionally substituted methyl group andwherein, if the radicals R₁ and R₂ are separate, R₁ is hydrogen and R₂is optionally substituted phenyl, thienyl or furyl, and if the radicalsR₁ and R₂ are linked, they form, together with the carbon atom, anoptionally substituted cycloalkyl ring of 4 to 7 carbon atoms, andwherein B represents a radical with at most 20, above all at most 10,carbon atoms which is bonded via a sulphur atom or is bonded to oxygenor sulphur with the interposition of an optionally substituted CH₂group.

Substituents of the abovementioned cyclic radicals R₂ or R.sub. 1 +R.sub. 2 are, for example, lower alkyl such as methyl, lower alkoxy suchas methoxy, halogen atoms, for example fluorine or chlorine,trifluoromethyl, the nitro group and above all carbamoyl and acyl,especially lower alkanoyl such as acetyl, acylamino, especially loweralkanoylamino and lower alkoxycarbonylamino, for example acetylamino,tert.butoxycarbonylamino, di-lower alkylamino, for exampledimethylamino, lower alkanoyloxy such as acetoxy and loweralkoxycarbonyl, such as methoxycarbonyl. The cyclic radicals arepreferably unsubstituted. R₁ and R₂ together with the carbon atomrepresent above all cyclopentyl or cyclohexyl. If R₂ represents thienylor furyl, these radicals are bonded in the 2- or 3-position, preferablyin the 2-position.

Above all, R₁ represents hydrogen and R₂ represents unsubstitutedphenyl.

B denotes a radical of the general formula Ic ##EQU4## wherein n = 0 or1 and X represents sulphur if n = 0, or represents carbonyloxy(--CO--O--) or sulphonyl (SO₂) if n = 1, and wherein R₆ represents aorganic radical and R₅ represents hydrogen or an organic radical. If n =1, B therefore represents ##EQU5## wherein R₅ and R₆ have the indicatedmeaning.

An organic radical R₆ is an optionally substituted aliphatic,cycloaliphatic, cycloaliphatic-aliphatic, aromatic or araliphatichydrocarbon radical or a heterocyclic or heterocyclic-aliphatic radical.

An aliphatic hydrocarbon radical R₆ is above all a lower alkyl radical,especially a radical with 1-4 carbon atoms such as methyl, ethyl,propyl, isopropyl, n-butyl and tert. butyl. Such a radical is preferablyunsubstituted but can also be substituted by one or more substituents.

As substituents there are to be mentioned free, esterified or etherifiedhydroxyl or mercapto groups such as halogen (with an atomic weight of atmost 127), especially chlorine or fluorine, acyloxy, above all loweralkanoyloxy such as acetoxy or aroyloxy such as benzoyloxy, lower alkoxysuch as methoxy, aryloxy such as phenoxy which is optionallysubstituted, especially by halogen, nitro, lower alkyl or lower alkoxy,for example p-chlorophenoxy, lower alkylmercapto such as methylmercapto,and also trifluoromethyl, free or functionally modified carboxyl groups,for example ester groups, especially lower alkoxycarbonyl such asmethoxycarbonyl, nitrile, optionally substituted carbamoyl, for exampleN-lower alkylcarbamoyl such as N-methylcarbamoyl, the nitro group andacyl groups, especially acyl of carboxylic acids, for example loweralkanoyl such as acetyl or monocyclic aroyl such as benzoyl.

A cycloaliphatic hydrocarbon radical R₆ is, for example, a cycloalkyl orcycloalkenyl radical with 3-8, preferably 5-6, carbon atoms, for examplecyclohexyl and cyclohexenyl; a cycloaliphatic-aliphatic hydrocarbonradical is, for example, a cycloalkyl- or cycloalkenyl-lower alkylradical, wherein cycloalkyl, cycloalkenyl and lower alkyl have theindicated meanings, for example cyclopentylmethyl andcyclohexenylmethyl. These radicals can be substituted in the same manneras the aliphatic hydrocarbon radicals described above; they can alsopossess lower alkyl groups, for example methyl, ethyl or tert.-butyl, assubstituents.

An aromatic radical R₆ is a monocyclic or bicyclic radical, for examplenaphthyl and preferably phenyl. These radicals can be substituted in thesame manner as the cyclic aliphatic radicals. Substituents arepreferably halogen, above all chlorine, nitro, lower alkyl and loweralkoxy.

Aliphatic radicals R₆ can also be monocyclic or bicyclic. Above all,they are phenyl-lower alkyl radicals such as benzyl or phenylethyl.These radicals, also, can carry the substituents indicated above for thealiphatic cyclic radicals, and especially the substituents preferred foraromatic radicals.

Heterocyclic radicals R₆ ae are or bicyclic radicals which containnitrogen, sulphur and/or oxygen as hetero-atoms. They possess 5-8,preferably 5-6, ring members per ring. They can be saturated orunsaturated. Preferably, they are of aromatic character. They possess1-4, preferably 1-2, hetero-atoms, above all of hetero-atom. They canpossess a fused benzene ring. As examples there should be mentioned:furyl, thienyl, pyrryl, indolyl, oxazolyl, thiazolyl, imidazolyl,pyrazolyl, triazolyl, tetrazolyl, thiadiazolyl, thiazolidinyl,tetrahydrofuranyl, pyrrolidyl, pyridyl, quinolyl, isoqinolyl,tetrahydropyranyl, pyrimidyl, pyridazinyl, pyrazinyl, triazinyl,tetrazinyl, piperidyl, morpholinyl and thiamorpholinyl, The rings canpossess substituents, as indicated above for the cycloaliphatic rings.

Heterocyclyl-aliphatic radicals R₆ are above all heterocyclyl-loweralkyl radicals, for example heterocyclyl-methyl radicals. Therein, theheterocyclyl radical is a radical such as descried above. These radicalscan also carry the substituents indicated above for cycloaliphaticradicals.

R₅ in the above formula I_(c) denotes, as already mentioned, hydrogen oran organic radical. The organic radical can have the same meaning asindicated for R₆. R₅ and R₆ can be identical or different. Preferably,R₅ represents hydrogen, lower alkyl, above all methyl, phenyl or5-6-membered heterocyclyl with one hetero-atom, for example thienyl,furyl and pyridyl.

The substituent R₃ present in the penicillanic acid derivatives andcephalosporanic acid derivatives of the formulae Ia and Ib is, as hasbeen mentioned, a free or protected carboxyl group. By a protectedcarboxyl group there is here to be understood a functionally modifiedcarboxyl group, such as an esterified or amidised carboxyl group, or acarboxyl group present in the anhydride form.

An esterified carboxyl group R₃ is preferably a group which can be spliteasily, for example a group which can be split, if necessary in an acidor weakly alkaline medium, solvolytically, for example by hydrolysis oralcoholysis, hydrogenolytically, reductively, by nucleophilic exchange,photolytically or enzymetically, to give the free carboxyl group.

Ester groups which can easily be split by solvolysis with a solventcontaining hydroxyl groups, for example water or alcohols such as, forexample, methanol or ethanol, preferably under neutral conditions, areabove all those which are derived from silyl, germanyl, plumbyl orstannyl alcohol. Such groups are described, for example, in BritishPatent Specification No. 1,073,530, in Netherlands PublishedSpecification No. 67/17, 107 and in German Offenlegungsschrift No.1,800,698. In particular, groups of the formula R₇ R₈ R₉ Si--OCO-- or R₇R₈ R₉ Sn--OCO-- can be used, wherein R₇ ; R₈ and R are identical ordifferent and represent alkyl, especially lower alkyl, aryl, for examplephenyl, or aralkyl such as phenyl-lower alkyl, such as benzyl.

Esters which are split easily in an acid medium, for example in thepresence of hydrogen chloride, hydrogen fluoride or hydrogen bromide, orof organic acids such as acetic acid, trifluoroacetic acid, formic acidor their mixtures with water, are above all those which are derived fromlower alkanols which are poly-branched in the α-position or loweralkanols which contain, in the α-position, one or more electron donorssuch as optionally substituted aromatic hydrocarbon radicals orheterocyclyl radicals of aromatic character, such as phenyl, furyl orthienyl or aroyl radicals such as benzoyl or acyloxy radicals such asaroyloxy or lower alkanoyloxy. Such ester groups are, for example tert.butoxycarbonyl, tert. amyloxycarbonyl, cyclopentyloxycarbonyl,cyclohexyloxycarbonyl, adamantyloxycarbonyl, furfuryloxycarbonyl,2-tetrahydrofuryloxycarbonyl, 2-tetrahydropyranyloxycarbonyl,benzyloxycarbonyl, p-nitrobenzyloxycarbonyl,p-methoxy-benzyloxycarbonyl, α-methyl-α-biphenylyl-methoxycarbonyl,3,4-dimethoxybenzyloxycarbonyl, 3,5-dimethoxybenzyloxycarbonyl,diphenylmethoxycarbonyl, di(p-methoxyphenyl)-methoxycarbonyl,triphenylmethoxycarbonyl, benzoylmethoxycarbonyl,benzoyloxymethoxycarbonyl, acetoxymethylcarbonyl andpivaloyloxymethoxycarbonyl.

Ester groups which can be split hydrolytically under weakly basic oracid conditions are, for example, activated esters which are derivedfrom optionally substituted phenol or benzyl alcohol, such as4-nitrophenyl, 2,4-dinitrophenyl, 4-nitrobenzyl, 2,4,6-trichlorophenyl,and 2,3,4,5,6-pentachlorophenyl esters, and also, for example,phthaliminomethyl, succiniminomethyl, triphenylmethyl andbis-(4-methoxyphenoxy)-methyl esters.

Examples of ester groups which can be split by hydrogenolysis are thosederived from optionally substituted benzyl alcohol, for examplep-nitrobenzyl alcohol. Ester groups which can be split reductivelywithout the conjoint use of catalysts, for example by treatment withnascent hydrogen, or by electrolytic reduction, are of greaterimportance. Such groups are derived, above all, from 2-halogeno-loweralkanols, for example from 2,2,2-trichloroethanol, 2-cloroethanol,2-bromoethanol and 2-iodoethanol and also, for example, frombenzoylmethanol or 4-pyridylmethanol. These alcohol groups can beremoved by treatment with chemical reducing agents, preferably underneutral or weakly acid conditions, for example with zinc in the presenceof aqueous acetic acid or formic acid or zinc in a lower alkanol or inpyridine, or by means of chromium-(II) reagents. The 4-pyridylmethoxygroup is appropriately removed by electrolytic reduction.

Ester groups which can easily be split off photolytically, especially byirradiation with ultraviolet light, preferably under neutral or acidconditions, are derived from methanols containing one or two arylradicals which are substituted, for example, by lower alkoxy groupsespecially methoxy and/or nitro groups. Such groups are above all3-methoxy- and 4-methoxy-benzloxycarbonyl, 3,4-dimethoxy- and3,5-dimethoxy-benzyloxycarbonyl, 2-nitrobenzyloxycarbonyl,4,5-dimethoxy-2-nitrobenzyloxycarbonyl,α-phenyl-α-(3,4-dimethoxy-6-nitro-phenyl)-methoxycarbonyl andα-methyl-α- (3,4-dimethoxy-6-nitrophenyl)-methoxycarbonyl.

Esters which can be split enzymatically are above all those whichcontain an ester group which can be split under physiologicalconditions. These esters can be resorbed well in the organism and aretherefore therapeutically usable as such. Esters of this nature aredescribed, for example, in British Patent Specification No. 1,229,453and in German Patent Application DT No. 1,951,012. The esters arederived from alcohols of the formula HO--CH₂ OCO--OCO--R₃ ", wherein R₃" can represent a hydrogen atom, an alkyl radical, a cycloalkyl radical,a cycloalkylalkyl radical, an aryl radical, an aralkyl radical or aheterocyclyl radical. In particular, R₃ " can represent a lower alkylradical with at most 5 carbon atoms such as methyl, ethyl, propyl,isopropyl, butyl, isobutyl and above all tert.-butyl, and also amonocyclic cycloalkyl radical with 3 to 7 carbon atoms; a bicycliccycloalkyl radical, such as a 1-bicyclo-(2,2,)-octyl or adamantylradical; a monocyclic aryl radical, for example an optionallysubstituted phenyl radical; a bicyclic aryl radical, such as a1-naphthyl radical, a 2-naphthyl radical or a substituted naphthylradical; a monocyclic or bicyclic aralkyl radical, for example a benzylor phenylethyl radical or a naphthyl-lower alkyl radical, such asnaphthylmethyl. R₃ " can also represent a heterocyclyl radical with 5-6ring atoms and at least one nitrogen, sulphur or oxygen atom, forexample thienyl, furyl, pyrryl, oxazolyl, thiazolyl and imidazolyl.

Examples of substituents in the above ring systems which form a part ofR₃ are, inter alia, lower alkyl radicals, lower alkoxy radicals, loweralkylmercapto radicals, lower halogenoalkyl radicals, such asmonohalogenoalkyl, dihalogenoalkyl or trihalogenoalkyl radicals, inwhich the halogen can be fluorine, chlorine or bromine, and nitrogroups. Processes for the manufacture of the above esters are describedin the British Patent Specification and German Application which havebeen mentioned.

The carboxyl group R₃ can also be esterified by a lower alkanol such asmethanol or ethanol.

In the amidised carboxyl group R₃ the amide nitrogen atom can optionallybe substituted, for example by monovalent or bivalent aliphatichydrocarbon radicals which can optionally be interrupted by oxygen,nitrogen or sulphur atoms. Such radicals are above all lower alkyl, forexample as mentioned above, especially methyl, or lower alkylene, forexample 1,4-butylene or 1,5-pentylene, oxa-lower alkylene, for example3-oxo-1,5-pentylene, or aza-lower alkylene, for example3-methyl-3-aza-1,5-pentylene.

A protected carboxyl group R₃ present in the anhydride form, preferablyin the form of a mixed anhydride, is above all a group which can besplit hydrolytically. The second acyl radical is, for example, the acylradical of a carboxylic acid, especially of a lower alkanoic acid whichis optionally substituted, for example by halogen, for example acetyl,trichloroacetyl or pivaloyl, or the acyl radical of a carbonic acidmonoester, especially of a mono-lower alkyl ester, for exampleethoxycarbonyl or isobutyoxycarbonyl.

The radical R₄ in the cephalosporanic acid derivatives of the formula Ibrepresents, as mentioned, a hydrogen atom (with the side chain in the3-position of Cephalosporin C missing) or an unsubstituted orsubstituted methyl group. Substituents of the methyl group are above alla free, esterified or etherified hydroxyl group, an etherified mercaptogroup, an optionally N-substituted carbamoyloxy or thiocarbamoylmercaptogroup, a quaternary ammonium group or the nitrile group.

An esterified hydroxyl group contains, as the acid radical, above allthe radical of a carboxylic acid or thiocarboxylic acid, for examplelower alkanoyl which is optionally substituted by halogen atoms,especially chlorine, such as formyl, priopionyl, butyryl, pivaloyl andchloroacetyl, but especially acetyl, or aroyl or aryl-lower alkanoylwhich are optionally substituted, for example by lower alkyl, loweralkoxy, halogen or nitro, for example benzoyl or phenylacetyl, and also,as a thiocarboxylic acid radical, especially aroylthio which isoptionally substituted as mentioned, above all benzoylthio.Additionally, hydroxyl groups esterified by hydrogen halide acids shouldbe mentioned; the methyl group R₄ can therefore be substituted, forexample by fluorine, chlorine or bromine.

Etherified hydroxyl groups are described, for example, in Belgian PatentNo. 719,710. Lower alkoxy, such as methoxy, ethoxy and n-propoxy,furanyl and pyranyl should be singled out.

Etherified mercapto groups for example contain, as etherifying radicals,lower alkyl, for example methyl, and also optionally substituted phenylor heterocyclyl, wherein the substituents can be the same as indicatedabove for the aromatic and heterocyclic radicals R₆. The heterocyclylradicals preferably have 5-6 ring atoms and contain, as hetero-atoms,nitrogen, optionally in the N-oxidised form, and/or oxygen or sulphur.Examples to be mentioned are 1-oxidised 2-pyridyl, pyrimidyl,pyridazinyl, pyrazinyl, imidazolyl, imidazolidyl, and purinyl.Optionally substituted heterocyclyl radicals of aromatic character with5 ring atoms, which contain at least 2 nitrogen atoms and furthermore anadditional hetero-atom from the group of nitrogen, oxygen and sulphur,should be singled out particularly. preferred substituents are loweralkyl radicals with 1-5 carbon atoms, such as methyl, ethyl, propyl,isopropyl, n-butyl, isobutyl and tert. butyl, lower alkoxy and loweralkylthio radicals with 1-5 carbon atoms, especially methylthio,cycloalkyl radicals such as cyclopentyl and cyclohexyl, or aryl radicalssuch as phenyl or substituted phenyl, for example phenyl substituted byone or more nitro groups or halogen atoms or lower alkyl or lower alkoxygroups, or unsubstituted or substituted thienyl, especially thienyl-(2),or thienyl substituted as indicated for phenyl, or optionallymonosubstituted or disubstituted amino groups, for example acetylamino,tert.butoxycarbonylamino, tert.-amyloxycarbonylamino and sulphonylamino.As examples of the heterocyclyl radical there should be mentioned:1H-1,2,3-triazol-5-yl, 1,3,4-triazol-2-yl, 5-methyl-1,3,4-triazol-2-yl,1H-1,2,4-triazol-5-yl, 1-phenyl-3-methyl1H-1,2,4-triazol-5-yl,4,5-dimethyl-4H-1,2,4-triazol-3-yl, 4-phenyl-4H-1,2,4-triazol-3-yl,1H-tetrazol-5-yl, 1-methyl-1H-tetrazol-5-yl, 1-ethyl-1H-tetrazol-5-yl,1-n-propyl-1H-tetrazol-5-yl, 1-isopropyl-1H-tetrazol-5-yl,1-n-butyl-1H-tetrazol-5-yl, 1-cyclopentyl-1H-tetrazol-5-yl,1-phenyl-1H-tetrazol-5-yl, 1-p-chlorophenyl-1H-tetrazol-5-yl,1,2,3-thiadiazol-5-yl, 1,3,4-thiadiazol-2-yl, 1,2,4-thiadiazol-3-yl,1,2,4-thiadiazol-5-yl, 3-methyl-1,2,4-thiadiazol-5-yl,2-methyl-1,3,4-thiadiazol-5-yl, 2-methylthio-1,3,4-thiadiazol-5-yl,2-ethyl-1,3,4-thiadiazol-5-yl, 2-n-propyl-1,3,4-thiadiazol-5-yl,2-isopropyl-1,3,4-thiadiazol-5-yl, 2-phenyl-1,3,4-thiadiazol-5-yl,1,2,4-oxadiazol-5-yl, 1,2,3-oxadiazol-5-yl, 1,3,4-oxadiazol-5-yl,2-methyl-1,3,4-oxadiazol-5-yl, 2-ethyl-1,3,4-oxadiazol-5-yl,2-phenyl-1,3,4-oxadiazol-5-yl, 2-p-nitrophenyl-1,3,4-oxadiazol-5-yl,2-[thienyl(2)]- ,3,4-oxadiazol-5-yl and thiatriazol-5-yl.

An optionally N-substituted carbamoyloxy group or thiocarbamoylmercaptogroup is, for example, a group of the formula --O--CO--NH--R₁₀ or##EQU6## wherein R₁₀ 10 is an optionally halogen-substituted lower alkylradical and R₁₁ is hydrogen or R₁₀. Above all, r₁₀ is methyl, ethyl orchlorine-substitued methyl or ethyl, especially β-chloroethyl.

In a quaternary ammonium-methyl group R₄ the ammonium part is preferablya pyridinium group which is optionally substituted, for example by loweralkyl, as mentioned above, or by optionally substituted carboxyl, suchas lower alkoxycarbonyl, for example ethoxycarbonyl, or carbamoyl.

Salts of compounds of the present invention are above allpharmaceutically usable non-toxic salts of those compounds which canform salts with bases. Such salts are above all metal salts or ammoniumsalts, such as alkali metal salts, alkaline earth metal salts and earthmetal salts, for example sodium, potassium, magnesium, calcium oraluminium salts, as well as ammonium salts with ammonia or suitableorganic bases, in which case it is possible to use for the saltformation above all aliphatic, cycloaliphatic, cycloaliphatic-aliphaticand araliphatic primary, secondary or tertiary monoamines, diamines orpolyamines, as well as heterocyclic bases, such as lower alkylamines,for example triethylamine, hydroxy-lower alkylamines, for example2-hydroxyethylamine, bis-(2-hydroxyethyl)-amine ortri-(2-hydroxyethyl)-amine, basic aliphatic esters of carboxylic acids,for example 4-aminobenzoic acid 2-diethylaminoethyl ester, loweralkyleneamines, for example 1-ethylpiperidine, cycloalkylamines, forexample bicyclohexylamine, or benzylamines, for exampleN,N'-dienzylethylenediamine, and also bases of the pyridine type, forexample pyridine, collidine or quinoline.

The new compounds can be in the form of mixtures of isomers, for exampleracemates, or of individual isomers, for example optically activeantipodes.

The new compounds of the formula I display a pharmacological action,especially a particularly pronounced anti-bacterial action. Thus theyare active against gram-positive bacteria, such as Staphylococcusaureus, but above all against gram-negative bacteria, for exampleEscheria coli, Klebsiella pneumonia, and Salmonella typhosa, andespecially against Bacterium proteus as well as Pseudomonas aeruginosa.Thus they inhibit the growth of Pseudomonas aeruginosa at dilutions downto 0.4 γ/ml. They can therefore be used for combating infections whichare caused by such micro-organisms, and also be used as fodderadditives, for the preservation of foodstuffs or as disinfectants.

Compounds to be singled out are 3-cephem compounds of the formula##EQU7## and especially penam compounds of the formula ##EQU8## whereinR₃ ' in particular is hydroxyl or lower alkoxy, for example methoxy ortert.-butoxy, 2-halogeno-lower alkoxy, for example2,2,2-trichloroethoxy, 2-bromoethoxy or 2-iodoethoxy, phenacyloxy,phenyl-lower alkoxy, for example benzyloxy or diphenylmethoxy, amino,lower alkylamino, for example methylamino, di-lower alkylamino, forexample dimethylamino, or morpholino, and R₄ ' represents hydrogen,methyl, lower alkanoyloxymethyl, for example acetoxymethyl,pyridiniummethyl, 1-oxydised 2-puridylthiomethyl,1,3,4-thiadiazol-2-ylthiomethyl,2-methyl-1,3,4-thiadiazol-5-ylthiomethyl,3-methyl-1,2,4-thiadiazol-5-ylthiomethyl or1-methyl-5-tetrazolylthiomethyl, and wherein B' represents --S--R₆ ',wherein R₅ ' represents hydrogen, lower alkyl, above all methyl, phenyl,thienyl, furyl or pyridal and R₆ ' has the following meanings:

a. A lower alkyl radical which is optionally substituted by halogen, forexample iodine, bromine or fluorine, but especially chlorine,trifluoromethyl, lower alkoxy such as methoxy, aryloxy such as phenoxyor lower alkanoyloxy such as acetoxy, above all methyl, ethyl,isopropyl, chloromethyl, dichloroethyl or phenoxymethyl; or

b. A phenyl, naphthyl or benzyl radical which is optionally substitutedby lower alkyl, for example methyl or ethyl, lower alkoxy, for examplemethoxy or ethoxy, halogen, for example chlorine or fluorine,trifluoromethyl or nitro, for example phenyl, naphthyl, benzyl,p-nitrophenyl or p-tert.-butylphenyl, or

c. An optionally substituted monocyclic heterocyclyl radical of aromaticcharacter with 1 - 2 ring hetero-atoms and 5 - 6 ring atoms or acorresponding heterocyclylmethyl radical wherein the substituents arethose mentioned under (b), above all furyl, thienyl, furfuryl, thenyl,pyridyl, pyrazinyl and pyrimidyl.

Penam compounds of the formula IB, wherein B' represents acetoxymethyl,α-acetoxyethyl, α-chloroacetoxy-ethyl, α-phenoxyacetoxy-ethyl,phenylsulphonylmethyl, p-tert.-butylphenylsulphonylmethyl,naphthylsulphonylmethyl or benzylthio, and wherein R₃ ' representshydroxy, as well as non-toxic salts such as alkali metal salts, forexample sodium salts or potassium salts, or alkaline earth metal salts,such as calcium salts, of these compounds, are therapeuticallyparticularly valuable.

The new compounds are manufactured according to methods which are inthemselves known. Thus they can be obtained if

a. a compound of the formula II ##EQU9## in which Z represents theradical ##EQU10## wherein R₁, R₂ and A have the meaning indicated forthe formula I, or a salt thereof, is reacted with an acyl-isocyanate ofthe formula III

    o = c = n -- co -- b                                       iii

wherein B has the meaning indicated for the formula I, or

b. a compound of the formula II, wherein Z represents hydrogen, isN-acylated with an acyl radical of the formula IV ##EQU11## wherein B,R₁ and R₂ have the meaning indicated for the formula I and, if desired,in a resulting compound of the formula Ia or Ib an optionallyfunctionally modified carboxyl group R₃ is converted into another R₃group and/or an optionally substituted methyl group R₄ is converted intoanother R₄ group and/or, if desired, a compound obtained as the freeacid is converted into a salt or a salt obtained is converted into thefree acid and/or an isomer mixture obtained is separated into theindividual isomers.

In a starting material of the formula II the group R₃ in the radical--S--A-- denotes, for example, one of the above-mentioned functionallymodified, especially esterified, carboxyl groups, such as a carboxylgroup esterified by di-lower alkylhalogenosilyl or tri-lower alkylsilyl,but preferably a free carboxyl group. A N-silylated or N-stannylatedderivative of a starting material contains, for example, theabovementioned organic silyl or stannyl radicals, such as tri-loweralkylsilyl, for example trimethylsilyl, bonded to the amino group. Saltsof starting compounds of the formula II are, in particular, those ofcompounds having a free carboxyl group, above all ammonium salts, suchas tri-lower alkyl ammonium salts, for example triethyl ammonium salts,and also alkali metal salts.

The reaction of the compound II with the acyl-isocyanate according to(a) is carried out in a manner which is in itself known. The solventsused are, for example, halogenated, especially chlorinated, hydrocarbonssuch as methylene chloride, chloroform, carbon tetrachloride,ethylenedichloride or ethylene tetrachloride, or hydrocarbons such asbenzene, and also, for example, acetonitrile, tetrahydrofurane, ether ormixtures of these solvents. The reaction is preferably carried out inthe presence of a base, for example a tertiary organic nitrogen basesuch as triethylamine, diisopropylethylamine, N,N-diethylaminoaceticacid ethyl ester, N-ethylmorpholine, N,N-dimethylaniline, pyridine,p-dimethylaminopyridine, collidine or 2,6-lutidine. It is carried out atroom temperature or slightly elevated temperature or, preferably, withcooling, for example at temperatures of -40° to +60°C. Theacylisocyanates of the formula III are known or can be manufactured in aknown manner. Thus, they can be obtained by reaction of acid halides,for example acid chlorides, with silver cyanate. Preferably, they aremanufactured according to the process described by A. J. Speciale et al.(J. Org. Chem. 30, 4306 (1965)) by reaction of primary amides of theformula B--CO--NH₂ , wherein B has the indicated meaning, with oxalylchloride. The reaction is carried out in an inert solvent, preferablyhalogenated hydrocarbon such as indicated above. It is conducted withexclusion of moisture, at temperatures of approx. 20° - 120° C. Theacyl-isocyanates do not have to be isolated but can, for example, beused in the form of solutions or suspensions in which they are obtainedduring their manufacture.

The acylation of the compound II according to (b) with the acyl radicalIV is carried out according to methods which are in themselves known,especially in the manner known from peptide chemistry for the acylationof weakly basic amino groups. The acylating agent used which containsthe acyl radical IV is either the corresponding acid, in which case thereaction is carried out in the presence of a condensation agent, forexample a carbodiimide, such as dicyclohexylcarbodiimide, or of Woodwardreagent K or L, or a reactive acid derivative, for example an acidhalide, especially an acid chloride or bromide, an acid azide, anactivated ester or a mixed anhydride, for example an anhydride with amono-esterified carbonic acid such as a carbonic acid lower alkyl ester,for example carbonic acid methyl ester, or with an optionallyhalogen-substituted lower alkanoic acid such as formic acid, pivalicacid or trichloroacetic acid. Above all, an activated ester is used forthe acylation, especially the p-nitrophenyl ester, 2,4-dinitrophenylester, 2,4,5- or 2,4,6-trichlorophenyl ester or pentachlorophenyl ester,and also, for example, the cyanomethyl ester, N-hydroxysuccinimideester, N-hydroxypiperidine ester and N-hydroxyphthalimide ester.

The acylation reaction is carried out in the presence of a solvent ordiluent, if desired in the presence of a catalyst and/or in the presenceof basic agents such as aliphatic, aromatic or heterocyclic nitrogenbases, for example triethylamine, diisopropylethylamine,N,N-diethylaminoacetic acid ethyl ester, N-ethylmorpholine,N,N-dimethylaniline, pyridine, 2-hydroxypyridine,p-dimethylaminopyridine, collidine and 2,6-lutidine.

The reaction is carried out at room temperature or with cooling orwarming, for example at temperatures of -70° to +100°C, if appropriatein an inert gas atmosphere, for example a nitrogen atmosphere and/orwith exclusion of moisture.

The acylating agents are known or can be manufactured in a manner whichis in itself known.

A derivative which is suitable for introducing the acyl group IV,especially an activated ester, for example of the formula ##EQU12##wherein Ph represents a nitro-substituted or halogen-substituted phenylradical, and B, R₁ and R₂ have the above-mentioned meaning can beobtained, for example, by reaction of the ester ##EQU13## with theacylisocyanate B -- CO -- N = C = O.

In the reaction (a) or (b), free hydroxyl, mercapto, amino and/orcarboxyl groups which may be present in the reactants are appropriatelyprotected, especially by protective groups which can easily be splitoff, such as are known, for example, from the synthesis of peptides,compare Schroder and Lubke "The Peptides", Vol. I, Academic Press, NewYork and London, 1965, and Th. Wieland, Angew. Chem. 63 (1951) 7-14, 66(1954), 507-512, 69 (1957), 362-372, 71 (1959), 417-425 and 75 (1963),539-551. As amino-protective groups there should be mentioned, forexample, optionally substituted aralkyl groups such as diphenylmethyl ortriphenylmethyl groups, or acyl groups such as formyl, trifluoroacetyl,phthaloyl, p-toluenesulphonyl, benzylsulphonyl, benzenesulphenyl oro-nitrophenylsulphenyl, or above all groups which are derived fromcarbonic acid or thiocarbonic acid, such as carbobenzoxy groups whichare optionally substituted in the aromatic radical by halogen atoms,nitro groups, lower alkyl or lower alkoxy or lower carbalkoxy groups,for example carbobenzoxy, p-bromocarbobenzoxy or p-chlorocarbobenzoxy,p-nitrocarbobenzoxy and p-methoxycarbobenzoxy, colouredbenzyloxycarbonyl groups such as p-phenylazo-benzyloxycarbonyl andp-(p'-methoxyphenylazo)-benzyloxycarbonyl, tolyloxycarbonyl,2-phenyl-isopropoxycarbonyl, 2-tolyl-isopropoxycarbonyl and above all2-(para-biphenylyl)-2-propoxycarbonyl, and also aliphatic oxycarbonylgroups such as, for example, allyloxycarbonyl, cyclopentyloxycarbonyl,tert.amyloxycarbonyl, adamantyloxycarbonyl,2,2,2-trichloroethoxycarbonyl, 2-iodoethoxycarbonyl and above alltert.butoxycarbonyl, and also, for example, carbamoyl, thiocarbamoyl,N-phenylcarbamoyl and N-phenylthiocarbamoyl. Ester groups for protectinga free carboxyl group, which can easily be split off, have already beenlisted above. Hydroxyl groups are preferably protected byetherification, for example with tert.butanol. Trityl, for example, issuitable as the mercapto protective group.

In a compound of the formula I obtained according to the invention, aprotected carboxyl group R₃, especially an esterified carboxyl groupwhich can easily be converted into the free carboxyl group, can beconverted in the abovementioned manner into the free carboxyl group. Itis also possible, before splitting off the ester group, to convert theester group into another ester group, for example to convert a2-bromoethyl ester group into a 2-iodoethyl ester group.

In a compound of the formula I obtained according to the process or acompound of the formula II used as the starting material, wherein R₃represents a free carboxyl group, the latter can be converted in amanner which is in itself known into a protected carboxyl group,especially a functionally modified carboxyl group. Thus, a free carboxylgroup can be esterified, for example by treatment with a diazo compound,such as a diazo-lower alkane, for example diazomethane or diazoethane,or a phenyl-diazo-lower alkane, for example phenyl-diazomethane ordiphenyldiazomethane, or by reaction with an alcohol suitable foresterification, in the presence of an esterifying agent, such as acarbodiimide, for example dicyclohexylcarbodiimide, as well ascarbonyldiimidazole, or in accordance with any other known and suitableesterification process, such as the reaction of a salt of the acid witha reactive ester of an alcohol with a strong inorganic acid or with astrong organic sulphonic acid. Furthermore, acid halides, such as acidchlorides (manufactured, for example, by treatment with oxalylchloride), activated esters (formed, for example, withN-hydroxy-nitrogen compounds) or mixed anhydrides (obtained, forexample, with halogenoformic acid lower alkyl esters, such aschloroformic acid ethyl ester, or with halogenoacetic acid halides, suchas trichloroacetic acid chloride) can be converted into an esterifiedcarboxyl group by reaction with alcohols, optionally in the presence ofa base, such as pyridine, and furthermore a mixed anhydride with acarbonic acid half ester can be converted into an esterified carboxylgroup by splitting off carbon dioxide.

Carboxyl groups esterified by organic silyl or stannyl groups can beformed in a manner which is in itself known, for example by treatingcompounds of the formula I or II, wherein R₃ represents a free carboxylgroup, or salts, such as alkali metal salts, for example sodium salts,thereof, with a suitable silylating agent, such as a di-loweralkyl-dihalogenosilane, for example dimethyldichlorosilane, a tri-loweralkylsilyl halide, for example trimethyl-silyl chloride, or anoptionally N-mono-lower alkylated, N,N-di-lower alkylated, N-tri-loweralkylsilylated or N-lower alkyl-N-tri-lower alkylsilylated N-(tri-loweralkylsilyl)-amine (see, for example, British Patent No. 1,073,530) orwith a suitable stannylating agent, such as a bis-(tri-lower alkyl-tin)oxide, for example bis-(tri-n-butyl-tin) oxide, a tri-lower alkyl-tinhydroxide, for example triethyl-tin hydroxide, a tri-lower alkyl-loweralkoxy-tin compound, tetra-lower alkoxy-tin compound or tetra-loweralkyl-tin compound, or a tri-lower alkyl-tin halide, for exampletri-n-butyl-tin chloride (see, for example, Netherlands PublishedSpecification No. 67/17,107).

Mixed anhydrides of compounds of the formula I or II, wherein R₃represents a free carboxyl group, can be manufactured by reacting such acompound or preferably a salt thereof, especially an alkali metal saltor ammonium salt thereof, with a reactive derivative, such as a halide,for example the chloride, of an acid, for example a halogenoformic acidlower alkyl ester or a lower alkanecarboxylic acid chloride.

A resulting compound of the formula I, wherein the group R₃ represents afree carboxyl group, can be converted into the corresponding amide in amanner which is in itself known. Thus it is possible, for example, totreat the acid or a corresponding acid halide or mixed anhydride or acorresponding ester, especially an activated ester, but also, forexample, a lower alkyl ester, such as the methyl ester or ethyl ester,with ammonia or a primary or secondary amine, and when using the acid asuitable condensation agent, such as a carbodiimide, for exampledicyclohexylcarbodiimide, is used. It is also possible to react the freecarboxylic acid with an isocyanate which is derived from thecorresponding amine and to convert the mixed anhydride formed into thedesired amide, whilst splitting off carbon dioxide.

In compounds of the formula I, wherein the fragment --S--A-- representsthe group of the formula Ib, a radical R₄ can be converted into anothergroup of this nature. Thus it is possible to treat a compound having anesterified hydroxymethyl radical R₄, wherein the esterified hydroxylgroup especially denotes lower alkanoyloxy, for example acetoxy, withpyridine at an elevated temperature, or first to react it withthiobenzoic acid and then to treat it with pyridine in the presence of amercury salt, or to react it with a suitable salt, such as potassiumthiocyanate, potassium iodide or potassium nitrate, and with pyridine inthe presence of water at a pH value of about 6.5 which is set up, forexample, with the aid of phosphoric acid, and thus to obtain thecorresponding pyridiniummethyl compound which can, if required, beconverted into the internal salt (zwitter-ion form), for example bytreatment with a suitable ion exchange reagent. Furthermore it ispossible to react compounds having a low alkanoyloxymethyl group, forexample acetoxymethyl group, as the radical R₄, with a mercaptocompound, such as an optionally substituted lower alkylmercaptan,phenylmercaptan or heterocyclomercaptan, and thus to obtain compounds ofthe formula I, wherein R₄ in a partial formula Ib represents anetherified mercapto group.

Salts of compounds of the formula I can be manufactured in a mannerwhich is in itself known. Thus it is possible to form salts of compoundsof the formula I, wherein R₃ represents a free carboxyl group, forexample by treatment with metal compounds, such as alkali metal salts ofsuitable carboxylic acids, for example the sodium salt ofα-ethyl-caproic acid, or with ammonia or a suitable organic amine.

Salts can be converted in the usual manner into the free compounds,metal and ammonium salts being converted, for example, by treatment withsuitable acids or ion exchangers.

Resulting mixtures of isomers can be separated into the individualisomers according to methods which are in themselves known, for exampleby fractional crystallisation, adsorption chromatography (columnchromatography or thin layer chromatography) or other suitable methodsof separation. Resulting racemates can be separated into the antipodesin the customary manner, if necessary after introduction of suitablesalt-forming groupings, for example by forming a mixture ofdiastereoisomeric salts with optically active salt-forming agents,separating the mixture into the diastereoisomeric salts and convertingthe separated salts into the free compounds, or by fractionalcrystallisation from optically active solvents.

The process also encompasses those embodiments according to whichcompounds which arise as intermediate products are used as startingsubstances and the remaining process steps are carried out with these,or the process is stopped at any stage; furthermore, starting substancescan be used in the form of derivatives or be formed during the reaction.

Preferably, such starting substances are used, and the reactionconditions are so chosen, that the compounds initially listed as beingparticularly preferred are obtained.

The starting substances of the formula II are known or can bemanufactured according to the processes already mentioned.

The new compounds can be used as medicines, for example in the formpharmaceutical preparations which contain an effective amount of theactive substance together with, or mixed with inorganic or organic,solid or liquid, pharmaceutically usable excipients which are suitablefor enteral or, preferably, parenteral administration. Thus, tablets orgelatine capsules are used which contain the active substance togetherwith diluents, for example lactose, dextrose, sucrose, mannitol,sorbitol, cellulose and/or glycine, and lubricants, for example silica,talc, stearic acid or salts thereof, such as magnesium stearate orcalcium stearate, and/or polyethylene glycol; tablets also containingbinders, for example magnesium aluminium silicate, starches, such ascorn starch, wheat starch, rice starch or arrowroot, gelatine,tragacanth, methylcellulose, sodium carboxymethylcellulose and/orpolyvinylpyrrolidone and, if desired, disintegrating agents, for examplestarches, agar, alginic acid or a salt thereof, such as sodium alginate,and/or effervescent mixtures, or adsorbents, dyestuffs, flavouringsubstances and sweeteners. Preferably, the pharmacologically activecompounds of the present invention are used in the form of injectable,for example intravenously administerable, preparations, or of infusionsolutions. Such solutions are preferably isotonic aqueous solutions orsuspensions which can, for example, be manufactured before use fromlyophilised preparations which contain the active substance alone ortogether with an excipient, for example mannitol. The pharmaceuticalpreparations can be sterilised and/or contain auxiliary substances, forexample preservatives, stabilisers, wetting agents and/or emulsifiers,solubilising agents, salts for regulating the osmotic pressure and/orbuffers. The present pharmaceutical preparations which can, if desired,contain further pharmacologically valuable substances, are manufacturedin a manner which is in itself known, for example by means ofconventional mixing, granulating, dragee-making, dissolving orlyophilising processes, and contain from about 0.1 to 100%, especiallyfrom about 1 percent to about 50%, of lyophilisates or up to 100% of theactive substance.

In the context of the present description, organic radicals described as"lower" contain up to 6, preferably up to 4, carbon atoms; acyl radicalscontain up to 20, preferably up to 12, carbon atoms.

The examples which follow serve to illustrate the invention.

The following systems are used in thin layer chromatography:

System

52A n-butanol-glacial acetic acid-water (67:10:23)

67 n-butanol-ethanol-water (40:10:50, upper phase)

101 n-butanol-pyridine-glacial acetic acid-water (38:24:8:30)

101A n-butanol-pyridine-glacial acetic acid-water (42:24:4:30).

In the Examples, "MIC" means the minimum inhibitory concentration inγ/ml which is measured by the gradient plate test described in"Antibiotics" Vol. I by Gottlieb and Shaw, New York, 1967, page 508, amodified method of that described by V. Bryson and R. Szybalski, Science116, 45 (1952). The MIC is determined on strains of Pseudomonasaeruginosa (Ps.aer.) ATCC 12055, Ps.aer. ATCC 10145, Ps.aer. Prof.Richmond, Pseudomonas aer. 313, Staphylococcus aureus (St.aur.) Smith14, Escherichia coli (E.coli) ATCC 2018, E.coli 205, Klebsiellapneumoniae (K.pn.) 327 and/or Salmonella typhimurium (S.typh.) 277.

EXAMPLE 1

A suspension of 1.70 g of anhydrous6-(D-α-phenylglycylamino)-penicillanic acid in 30 ml of methylenechloride is mixed at room temperature, whilst stirring and excludingmoisture, with 1.05 ml of triethylamine and then cooled to -10°C.Thereafter a solution of 1.07 g of acetoxyacetylisocyanate (manufacturedaccording to the method of A. J. Speziale et al, J. org. Chem. 30, 4306(1965)) in 10 ml of methylene chloride is added dropwise over the courseof 5 minutes to the clear solution at -10°C, whilst stirring andcooling. Care is taken that the internal temperature does not exceed0°C. The reaction mixture is stirred for 1 hour at 0°C and issubsequently extracted with 70 ml of phosphate buffer solution of pH7.5. The phosphate buffer solution is twice extracted with ethyl acetateand the aqueous phase is then covered with ethyl acetate, rendered acid(pH 2.5) by adding 20% strength phosphoric acid whilst stirring andcooling at 10°C by means of an ice bath, and extracted three times withethyl acetate. The ethyl acetate extracts are combined, twice washedwith 50 ml portions of sodium chloride solution and dried over sodiumsulphate, and the solvent is evaporated off on a rotary evaporator at45°C. The product which remains is purified by precipitation frompetroleum ether.6-[D(-)-α(3-Acetoxyacetyl-1-ureido)-phenylacetamido]-penicillanic acidmelts at: 151°-155°C (with decomposition).

Thin layer chromatogram on silica gel: Rf_(52A) = 0.62, Rf₁₀₁ = 0.60,Rf₆₇ = 0.23, Rf_(101A) = 0.55. [α]_(D) ²⁰ = +166° ±1° (c = 1.00 in 0.5 NNaHCO₃). MIC Ps.aer. 12055 = 10; Ps.aer. 10145 = 30; Ps.aer. 313 = 30;St.aur. 14 = 1; E.coli 2018 = 4; Kl.pn. 327 = 50; S.typh. 277 = 40;

Manufacture of the acetoxyacetylisocyanate:

18.70 g of 2-(acetoxy)-acetamide are dissolved in 80 ml of1,1,2-trichloroethane, 17.0 ml of oxalyl chloride are then allowed torun in at room temperature whilst stirring and the reaction mixture isboiled for 2.5 hours under reflux. Thereafter the dark solution iscooled and fractionated at 50 mm Hg. Acetoxyacetylisocyanate boils at100°-103°C/50 mm Hg.

EXAMPLE 2

6-[D(-)-α-(3-Phenylsulphonylacetyl-1-ureido)-phenylacetamido]-penicillanicacid is obtained by reaction of 3.0 g of anhydrous6-(D-α-phenylglycylamino)-penicillanic acid in 40 ml of methylenechloride, in the presence of 1.80 ml of triethylamine, with a solutionof 2.10 g of phenylsulphonylacetylisocyanate in 15 ml of methylenechloride, as in Example 1. The crude product (4.0 g, 81% of theory) ispurified by filtration over a 40-fold amount of silica gel, using ethylacetate as the solvent, and subsequently by precipitation from ethylacetate solution by means of a mixture of ether and petroleum ether.

Melting point: 159°-161°C, with decomposition.

Thin layer chromatogram on silica gel: Rf₅₂ = 0.56, Rf₁₀₁ = 0.60, Rf₆₇ =0.31, Rf_(101A) = 0.54. [α]_(D) ²⁰ = +136° ±1° (c = 0.810 indimethylsulphoxide).

Manufacture of phenylsulphonylacetylisocyanate:

11.90 g of 2-(phenylsulphonyl)-acetamide are suspended in 100 ml ofethylene chloride, 7.70 ml of oxalyl chloride are then allowed to runinto the suspension at room temperature whilst stirring, and thereaction mixture is boiled for 5 hours under reflux. After evaporatingoff the solvent on a rotary evaporator at 60°C, the residual oil isfractionated at 0.8 mm Hg. During the entire reaction time, dry nitrogenis passed through the reaction mixture. Phenylsulphonylacetylisocyanateboils at 160°-1/3°C/0.8 mm Hg.

EXAMPLE 3

6-[D(-)-α(3-L(+)-α-Acetoxy-propionyl-1-ureido)--reido)-phenylacetamido]-penicillanic acid is obtained by reaction of20.0 g of anhydrous 6-(D-α-phenylglycylamino)-penicillanic acid in 300ml of methylene chloride, in the presence of 12.20 ml of triethylamine,with a solution of 11.00 g of L(+)-α-acetoxypropionylisocyanate in 70 mlof methylene chloride, as in Example 1.

The crude product (24.8 g, 85% of theory) is chromatographed on a30-fold amount of silica gel. The fractions eluted with a mixture ofmethylene chloride and methyl acetate (1:1) as the solvent are combined,the solvent is evaporated off on a rotary evaporator at 40°C and theresidual foam is purified by precipitation from ethyl acetate solutionby means of a mixture of ether and petroleum ether.

Melting point: 149 - 152°C, with decomposition.

Thin layer chromatogram on silica gel: Rf_(52a) = 0.70, Rf₁₀₁ = 0.67,Rf₆₇ = 0.45, Rf_(101A) = 0.61. [α]_(D) ²⁰ = +138° ± 1° (c = 1.030 in 0.5N NaHCO₃).

Manufacture of L(+)-α-acetoxypropionylisocyanate:

15.0 g of L(+)-acetyl-lactic acid amide are dissolved in 60 ml of1,1,2-trichloroethane, 12.80 ml of oxalyl chloride are then allowed torun in at room temperature whilst stirring and the reaction mixture isboiled under reflux for 5 hours. Thereafter the dark solution isfractionated at 50° mm Hg. During the entire reaction time, dry nitrogenis passed through the reaction mixture.L(+)-α-Acetoxypropionylisocyanate boils at 95°- 97°C/50 mm Hg.

EXAMPLE 4:

6-[D(-)-α-(3-α-Acetoxy-phenylacetyl-1-ureido)-phenylacetamido]-penicillanicacid is obtained by reaction of 3.49 g of anhydrous6-(α-phenylglycylamino)-penicillanic acid in 70 ml of methylenechloride, in the presence of 2.10 ml of triethylamine, with a solutionof 3.28 g of α-acetoxyphenylacetylisocyanate in 50 ml oftetrahydrofurane as in Example 1. The crude product (3.9 g, 70% oftheory) is purified by precipitation from ethyl acetate solution with amixture of ether and petroleum ether. Melting point: 157°-160°C, withdecomposition. Thin layer chromatogram on silica gel: Rf_(52A) = 0.63,Rf₁₀₁ = 0.60, Rf₆₇ = 0.35, Rf_(101A) = 0.57. [α]_(D) ²⁰ = +164°± 1 °(c =1.154 in dimethylsulphoxide).

Manufacture of α-acetoxyphenylacetylisocyanate:

13.50 g of acetylmandelic acid amide are dissolved in 60 ml of1,1,2-trichloroethane, 9.0 ml of oxalyl chloride are then allowed to runin at room temperature whilst stirring and the reaction mixture isboiled for 5 hours under reflux. Thereafter the solvent is evaporatedoff on a rotary evaporator at 60°C and the residual oil is fractionatedat 0.2 mm Hg. During the entire reaction time, dry nitrogen is passedthrough the reaction mixture. α-Acetoxyphenylacetylisocyanate boils at98°-100°C/0.2 mm Hg.

EXAMPLE 5

7-[D(-)-α-(3-Acetoxyacetyl-1-ureido)-phenylacetamido]cephalosporanicacid is obtained by reaction of 1.80 g of D(-)-cephaloglycine in 300 mlof methylene chloride, in the presence of 0.91 ml of triethylamine, witha solution of 0.93 g of acetoxyacetylisocyanate in 10 ml of methylenechloride, as in Example 1. The crude product (2.2 g, 89% of theory) ispurified by crystallisation from a mixture of tetrahydrofurane and ethylacetate. Melting point: 182°-185°C, with decomposition.

Thin layer chromatogram on silica gel: Rf_(52A) = 0.33, Rf₁₀₁ = 0.59,Rf₆₇ = 0.23, Rf_(101A) = 0.55. [α]_(D) ²⁰ = +56° ±1° (c = 1.027 indimethylsulphoxide).

EXAMPLE 6

Following the procedure of Example 1, 6-[D(-)-α-(3-p-tert.-butylphenylsulphonylacetyl-1-ureido)phenylactemido]-penicillanicacid is obtained by reaction of 6-(D-α-phenylglycylamino)-penicillanicacid with p-tert.butylphenylsulphonylacetyl-isocyanate (boiling point174°-176°C/1 mm Hg). Melting point 163°-165°C.[α]_(D) ²⁰ = +158° ±1° (c= 0.784 in dimethylsulphoxide). Rf_(52A) = 0.72; Rf₆₇ = 0.44; Rf₁₀₁ =0.63; Rf.sub. 101A = 0.68. MIC:Ps.aer. 12055 =15; Ps.aer.10145 = 15;Ps.aer. Richm. = 2; Ps.aer. 313 = 30; St.aur. 14 = 0.,3; E.coli 2018 =20; E.coli 205 = 20; K.pn. 327 = 35; S.typh. 277 = 30.

EXAMPLE 7

Following the procedure of Example 1,6-[D(-)-α-(3-L(+)-α-butyryloxy-propionyl-1-ureido)-phenylacetamido]-penicillanicacid is obtained by reaction of 6-(Dα-phenylglycylamino)-pencillanicacid with L(+)-α-butyryloxy-propionylisocyanate (boiling point90°-92°C/13 mmHg). Melting point 125°-130°C. [α]_(D) ²⁰ =+108° ±1° (c =1.166 in dimethylsulphoxide). Rf_(52A) = 0.66; Rf₆₇ = 0.42; Rf₁₀₁ =0.61; Rf_(101A) = 0.63

EXAMPLE 8

Following the procedure of Example 1,6-[D(-)-α-(3-L(+)-α-(2-furoyloxy)-propionyl-1-ureido)-phenylacetamido]-penicillanicacid is obtained by reaction of 6-(D-α-phenylglycylamino)-penicillanicacid with L(+)-α-(2-furoyloxy)-propionyl-isocyanate (boiling point99°-100°C/0.8 mm Hg). Melting point 148°-152°C.[α]_(D) ²⁰ = +221° ±1° (c= 1.176 in dimethylsulphoxide). Rf_(52A) = 0.78; Rf₆₇ = 0.45; Rf₁₀₁ =0.70; Rf_(101A) = 0.55.

EXAMPLE 9

Following the procedure of Example 1,6-[D(-)-α-(3-L(+)-α-(2-thenoyloxy)-propionyl-1-ureido)-phenylacetamido]-pencillanicacid is obtained by reaction of 6-(D-α-phenylglycylamino)-penicillanicacid with L(+)-α-(2-thenoyloxy)propionyl-isocyanate boiling point120°-121°C/1 mm Hg). Melting point 160°-163°C.[α]_(D) ²⁰ = +220° ±1° (c= 1.063 in dimethylsulphoxide). Rf_(52A) = 0.79; Rf₆₇ = 0.43; Rf₁₀₁ =0.70; Rf_(101A) = 0.55. MIC: Ps.aer.12055 = 10; Ps.aer.10145 = 10;Ps.aer.Richm. = 2; Ps.aer.313 = 10; St.aur.14 = 0.35; E.coli 2018 = 5;E.coli 205 = 4; K.pn.327 = 30; S.typh.277 = 20.

EXAMPLE 10

Following the procedure of Example 1,6-[D(-)-α-[3-D,L-α-acetoxy-(2-furylacetyl)-1-ureido]-phenylacetamido]-penicillanicacid is obtained by reaction of 6-(D-α-phenylglycylamino)-penicillanicacid with D,Lα-acetoxy-2-furylacetyl-isocyanate (boiling point95°-97°C/1 mm Hg). Melting point 152°-153°C. [α]_(D) ²⁰ = +150° ±1° (c =1.079 in dimethylsulphoxide). Rf_(52A) = 0.64; Rf₆₇ = 0.33; Rf₁₀₁ =0.57; Rf_(101A) = 0.62.

EXAMPLE 11

Following the procedure of Example 1,6-[D(-)-α-[3-D,L-α-acetoxy-(2-thienylacetyl)-1-ureido]-phenylacetamido]-penicillanicacid is obtained by reaction of 6-(D-α-phenylglycylamino)-penicillanicacid with D,L-α-acetoxy-2-thienylacetyl-isocyanate (boiling point113°-115°C/1 mm Hg). Melting point 150°-155°C. [α]_(D) ²⁰ = + 148° ± 1°(c = 1.014 in dimethylsulphoxide). Rf_(52A) = 0.67; Rf₆₇ = 0.32; Rf₁₀₁ =0.61; Rf_(101A) = 0.60.

EXAMPLE 12

Following the procedure of Example 1,6-[D(-)-α-(3-L(+)-α-(p-nitrobenzoyloxy)-propionyl-1-ureido)-phenylacetamido]-penicillanicacid is obtained by reaction of 6-(D-α-phenylglycylamino)-penicillanicacid with L(+)-α-(p-nitrobenzoyloxy)-propionyl-isocyanate (boiling point177°-178°C/1 mm Hg). Melting point 160°-170°C. [α]_(D) ²⁰ = ±1° (c =1.044 in dimethylsulphoxide). Rf_(52A) = 0.72; Rf₆₇ = 0.67; Rf₁₀₁ =0.63; Rf_(101A) = 0.64.

EXAMPLE 13

Following the procedure of Example 1,6-[D(-)-α-(3-L(+)-α-chloroacetoxy-propionyl-1-ureido)-phenylacetamido]-penicillanicacid is obtained by reaction of 6-(D-α-phenylglycylamino)-penicillanicacid with L-(+)-α-chloroacetoxypropionyl-isocyanate (boiling point113°-114°C/15 mm Hg). Melting point 125°-130°C [α]_(D) ²⁰ = 110° ± 1° (c= 0.996 in dimethylsulphoxide). Rf_(52A) = 0.68; Rf₆₇ = 0.35; Rf₁₀₁ =0.56; Rf_(101A) = 0.54. MIC: Ps.aer.12055 = 10; Ps.aer.10145 = 10;Ps.aer.Richm. = 3; Ps.aer.313 = 30; St.aur.14 = 0.3; E.coli 2018 = 4;E.coli 205 = 10; S.typh.277 = 10.

EXAMPLE 14

Following the procedure of Example 1,6-[D(-)-α-(3-L(+)-α-phenoxyacetoxy-propionyl-1-ureido)-phenylacetamido]-penicillanicacid is obtained by reaction of 6-(D-α-phenylglycylamino)-penicillanicacid with L-(+)-α-phenoxyacetoxypropionyl-isocyanate (boiling point135°-136°C/0.8 mm Hg; melting point 27°-29°C). Melting point 135°-140°C.[α]_(D) ²⁰ = + 134° (c = 1.226 in dimethylsulphoxide). Rf_(52A) = 0.70;Rf₆₇ = 0.42; Rf₁₀₁ = 0.59; Rf_(101A) = 0.61. MIC: Ps.aer.12055 = 10;Ps.aer.10145 = 10; Ps.aer.Richm. = 2; Ps.aer.313 =30; St.aur.14 = 0.06;E.coli 2018 = 3; E.coli 205 = 5; K.pn.327 = 20; S.typh.277 = 6.

EXAMPLE 15

Following the procedure of Example 1,6-[D(-)-α-(3-n-propylmercaptocarbonyl-1-ureido)-phenylacetamido]-penicillanicacid is obtained by reaction of 6-(D-α-phenylglycylamino)-penicillanicacid with n-propylmercaptocarbonyl-isocyanate (boiling point 95°-97°C/60mm Hg). Melting point 147°-149°C. [α]_(D) ²⁰ = + 196° ± 1° (c = 1.160 indimethylsulphoxide). Rf_(52A) = 0.70; Rf₆₇ = 0.45; Rf₁₀₁ = 0.65;Rf_(101A) = 0.61.

EXAMPLE 16

Following the procedure of Example 1,6-[D(-)-α-(3-benzylmercaptocarbonyl-1-ureido)-phenylacetamido]-penicillanicacid is obtained by reaction of 6-(D-α-phenylglycylamino)-penicillanicacid with benzylmercaptocarbonyl-isocyanate (boiling point 99°-100°C/2mm Hg). Melting point 140°-145°C. [α]_(D) ²⁰ = + 197° (c = 0.956 indimethylsulphoxide). Rf_(52A) = 0.68; Rf₆₇ = 0.43; Rf₁₀₁ = 0.60;Rf_(101A) = 0.59. MIC: Ps.aer.12055 = 6; Ps.aer.10145 = 6; Ps.aer.Richm.= 4; Ps.aer.313 = 20; St.aur.14 = 0.5; E.coli 2018 = 4; E.coli 205 = 5;K.pn.327 = 50; S.typh. 277 = 25.

EXAMPLE 17

Following the procedure of Example 1,6-[D(-)-α-(3-p-chlorophenylsulphonylacetyl-1-ureido)-phenylacetamido]-penicillanicacid is obtained by reaction of 6-(D-α-phenylglycylamino)-penicillanicacid with p-chlorophenylsulphonylacetyl-isocyanate (boiling point174°-176°C/1 mm Hg; melting point 58°-60°C). Melting point 158°- 161°C.[α]_(D) ²⁰ = + 146° (c = 0.983 in dimethylsulphoxide). Rf_(52A) = 0.68;Rf₆₇ = 0.38; Rf₁₀₁ = 0.59; R_(101A) = 0.52. MIC: Ps.aer.12055 = 10;Ps.aer.10145 = 20; Ps.aer. Richm. = 1.5; Ps.aer. 313 = 20; St.aur. 14 =0.15; E.coli 2018 = 4; E.coli 205 = 4; K.pn.327 = 20; S.typh.277 = 20.

EXAMPLE 18

Following the procedure of Example 1,6-[D(-)-α-(3-β'-naphthylsulphonylacetyl-1-ureido)-phenylacetamido]-penicillanicacid is obtained by reaction of 6-(D-α-phenylglycylamino)-penicillanicacid with β-naphthylsulphonylacetyl-isocyanate (melting point160°-164°C, from dichloroethylene). Melting point 152°-155°C. [α]_(D) ²⁰= + 110° (c = 0.902 in dimethylsulphoxide). Rf_(52A) = 0.73; Rf₆₇ =0.40; Rf₁₀₁ = 0.61. MIC: Ps.aer.12055 = 20; Ps.aer. 10145 = 20;Ps.aer.Richm. = 2; Ps.aer.313 = 25; St.aur. 14 = 0.2; E.coli 2018 = 5.5;E.coli 205 = 6.5; K.pn. 327 = 25; K.pn.277 = 20.

What we claim is:
 1. A compound of the formula ##EQU14## wherein R₃denotes a free carboxyl group and, if R₁ and R₂ are separate, R₁ ishydrogen and R₂ is phenyl, thienyl or furyl, and, if R₁ and R₂ arecombined, they form together with the carbon atom, cycloalkyl of 4 to 7carbon atoms, and wherein B denotes a radical of the formula ##EQU15##wherein x represents carbonyloxy or sulphonyl, R₅ represents hydrogen,lower alkyl, phenyl, thienyl, furyl or pyridyl and R₆ represents (a)lower alkyl or lower alkyl mono substituted by halogen, lower alkoxy,phenoxy or lower alkanoloxy or (b) phenyl, naphthyl, benzyl, furyl,thienyl, furfuryl, thenyl, pyridyl, pyrazinyl or pyrimidyl or phenyl,naphthyl, benzyl, furyl, thienyl, furfuryl, thenyl, pyridyl, pyrazinylor pyrimidyl mono substituted by lower alkyl, lower alkoxy, halogen ornitro, or a pharmaceutically acceptable salt thereof.
 2. A compoundaccording to claim 1 wherein R₃ denotes a free carboxyl group, R₁represents hydrogen and R₂ represents phenyl and B represents ##EQU16##and wherein R₅ ' represents hydrogen, lower alkyl, phenyl, thienyl,furyl or pyridyl and R₆ ' represents (a) lower alkyl or lower alkyl monosubstituted by halogen, lower alkoxy, phenoxy or lower alkanoloxy or (b)phenyl, naphthyl, benzyl, furyl, thienyl, furfuryl, thenyl, pyridyl,pyrazinyl or pyrimidyl or phenyl, naphthyl, benzyl, furyl, thienyl,furfuryl, thenyl, pyridyl, pyrazinyl or pyrimidyl mono substituted bylower alkyl, lower alkoxy, halogen or nitro.
 3. A compound according toclaim 1 wherein R₃ denotes a free carboxyl group, R₁ represents hydrogenand R₂ represents phenyl and B denotes lower alkanoyloxymethyl, α-loweralkanoyloxyethyl or α-lower alkanoyloxybenzyl.
 4. A compound accordingto claim 1 wherein R₃ denotes a free carboxyl group, R1 representshydrogen and R₂ represents phenyl and B denotes phenyl sulphonylmethylor naphthylsulphonylmethyl.
 5. A compound as claimed in claim 1, whichis 6-[D-α-(3-α-(2-thenoyloxy)- propionyl-1-ureido)-phenyl-acetamido]-penicillanic acid or a pharmaceutically acceptablesalt thereof.
 6. A compound as claimed in claim 1, which6-[D-α-(3-p-chlorophenylsulphonylacetyl-1-ureido)-phenylacetamido]-penicillanicacid or a pharmaceutically acceptable alkali metal, alkaline earthmetal, earth metal, ammonium or amine addition salt thereof.
 7. Acompound as claimed in claim 1 which is6-[D(-)-α-(3-L(+)-α-(2-furoyloxy)-propionyl-1-ureido)-phenylacetamido]-penicillanicacid or a pharmaceutically acceptable salt thereof.
 8. A compound asclaimed in claim 1, which is6-[D(-)-α-(3-D,L-α-acetoxy-(2-furylacetyl)-1-ureido-phenylacetamido]-penicillanicacid or a pharmaceutically acceptable salt thereof.
 9. A compound asclaimed in claim 1, which is6-[D(-)-α-(3-D,L-α-acetoxy-(2-thienylacetyl)-1-ureido)-phenylacetamido]-penicillanicacid or a pharmaceutically acceptable salt thereof.
 10. A compound asclaimed in claim 1, which is6-[D(-)-α-(3-L(+)-α-(p-nitrobenzoyloxy)-propionyl-1-ureido)-phenylacetamido]-penicillanicacid or a pharmaceutically acceptable salt thereof.
 11. A compound asclaimed in claim 1, which is6-[D(-)-α-(3-L(+)-α-chloroacetoxy-propionyl-1-ureido)-phenylacetamido]-penicillanicacid or a pharmaceutically acceptable salt thereof.
 12. A compound asclaimed in claim 1, which is6-[D(-)-α-(3-L(+)-α-phenoxyacetoxy-propionyl-1-ureido)-phenylacetamido]-penicillanicacid or pharmaceutically acceptable salt thereof.